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Tom Quinn and colleagues have found that two decades of carcasses — nearly 600,000 pounds of fish — tossed to the left side of Hansen Creek did have a noticeable effect: White spruce trees on that side of the stream grew faster than their counterparts on the other side.

Captive breeding programs are intended to rebuild highly endangered populations, but a major problem is how to reintroduce captive-bred individuals back to their native habitat. Often, there is low survival of reintroduced individuals compared to wild-born individuals. Such is the case for the critically endangered Vancouver Island marmot, which had shrunk to just 30 individuals in 2003. A new experiment compares survival to breeding age for three strategies: transferring wild-born individuals, translocating captive-born individuals to wild habitat, and a new stepping stone strategy that involved first transplanting captive born individuals to a safe wild area with high survival before transferring them in their second year to the lower-survival final destination.

A new study led by the University of Washington found that although dead whales are still valuable sources of fat and protein for some polar bears, this resource will likely not be enough to sustain most bear populations in the future when the Arctic becomes ice-free in summers, which is likely to occur by 2040 due to climate change. The results were published online Oct. 9 in the journal Frontiers in Ecology and the Environment.

In recent years there has been a growing debate about what proportion of the oceans is fished, with estimates ranging from well above 50% to just 4%. A new paper now looks at one of the most widespread and damaging fishing types, trawling, where a net is dragged over the sea bottom to capture fish. The new method focuses on shallower continental shelves that are less than 1000 m in depth, finding that the trawling footprint varies hugely across regions from 0.4% of the area to more than 80%, with an average of 14% for all regions examined.

A new analysis that uses high-resolution data for 24 ocean regions in Africa, Europe, North and South America and Australasia shows that 14 percent of the overall seafloor shallower than 1,000 meters (3,280 feet) is trawled. Most trawl fishing happens in this depth range along continental shelves and slopes in the world’s oceans. The study focused on this depth range, covering an area of about 7.8 million square kilometers of ocean.

Many fisheries around the world are not formally assessed, and for these fisheries it is hard to know whether they are overfished or not, and how much to fish to ensure that fishing remains sustainable. A suite of models has been developed that can be applied to fisheries where the only data available are time series of catches, but there is no information on trends in actual fish numbers.

Marine fisheries management aims to keep fish populations at sustainable levels while producing seafood. Fisheries that are assessed to be overfished must have their populations rebuilt to sustainable levels by reducing catches to lower levels. Usually the assessment of status relies on a complicated fisheries stock assessment model, sort of like a weather forecast for fisheries, that estimates the level of sustainable catch that can be taken from a fisheries population.

Bull trout use a bewildering array of strategies to aid in their survival, from remaining in streams their whole lives, like rainbow trout, to spending part of their lives in the ocean before returning to streams to spawn, just as salmon do. Bull trout are present in only one of two neighboring rivers in the Olympic peninsula, Washington state, and in this one (the Elwha River), two large dams were removed during the period 2011-2014.

For decades, fish researchers believed in Gerking’s “restricted movement paradigm”, thinking that river-dwelling fish largely stay in the same place and rarely venture forth. But in recent decades, ecologists have harnessed the power of both advanced tags and improved genetic methods to directly estimate movement distances and average home ranges of different fish species. Now, a new paper has gathered in one place data from more than 200 direct movement studies and more than 200 genetic studies to estimate how far river fish more on average.

The U.S. Endangered Species Act has saved or recovered many species, and is recognized as one of the most powerful laws in the world for protecting the environment. The primary aim of the Act is to ensure that populations and species persist, and to conserve genetic variation in population. But little attention is paid to the adaptive potential of populations—the capability of populations to evolve when faced with new selective pressures—even though new genetic methods of sequencing the entire DNA of organisms are now cheaper and easier than ever before.

The School of Aquatic and Fishery Sciences is dedicated to sustaining healthy marine and freshwater environments. Our faculty conduct innovative research from the organism to the ecosystem scale, and are recognized leaders in aquatic biology, sustainable fisheries management and aquatic resource conservation.